The present invention relates to management of data communication networks and, more particularly, virtual local area network (VLAN) and multicast group endpoint discovery in operator and service provider networks.
In an operator or service provider network, VLAN endpoint misconfigurations can cause serious problems. Since VLANs have precedence over Institute of Electrical and Electronics Engineers Std. 802.1ag (IEEE 802.1ag) maintenance levels, a misconfigured VLAN on an IEEE 802.1ag maintenance endpoint (MEP) can render the MEP unreachable and result in inadvertent connectivity loss alarms being reported by all other MEP at the same maintenance level. Moreover, a misconfigured VLAN can inadvertently allow unauthorized traffic to pass through a network endpoint or cause authorized traffic to be blocked by a network endpoint, resulting in potential security breaches or customer dissatisfaction. It is therefore desirable to discover and resolve VLAN endpoint misconfigurations at the earliest possible time, preferably before running IEEE 802.1ag connectivity fault management (CFM) or opening the network to external traffic.
In a service provider network, it is also desirable to learn multicast group endpoint configurations. For example, a service provider may want to monitor what multicast content its customers are viewing for security, billing, marketing or other purposes.
There are known protocols for transmitting VLAN configuration information. For example, in Cisco Systems, Inc.'s VLAN trunking protocol (VTP), when a new VLAN is configured on a switch, the new VLAN is advertised to other switches in the same domain. And in Cisco Systems, Inc.'s VLAN query protocol (VQP), a switch queries a VLAN membership policy server (VPMS) with a media access control (MAC) address of a LAN-attached node and, in response, is given a VLAN assignment for the switch port attached to the node. Neither VTP nor VQP provides for querying network endpoints to learn what VLANs are operative thereon and thereby learn of misconfigurations.
There are also known protocols for discovering node characteristics, such as eXchange IDentification (XID). In one implementation of XID, a resource may send an XID Command including a specified value to a node and the node may confirm support for the specified value by returning an XID Response including the specified value. XID is not, however, known to be VLAN or multicast group aware. Moreover, XID has no inherent mechanism to limit responses to a multicast XID Command strictly to endpoints. If an XID Command is multicast, then all XID-aware nodes on the path between the resource and the endpoints will respond, and the XID Command will even be propagated by the endpoints to the external network.